1. Field of the Invention
This invention relates to new and useful improvements in angle measuring instruments.
2. Background Information
There has been a need for an angle measuring device of simple construction that could quickly locate and read, inside and outside angles between two relative surfaces. There has also been a need for an angle gauge that could be easily operated with one hand and without the need for adjustment screws, alignment rods and levers, and other cumbersome means normally used with angle gauges currently available.
There has not been an angle gauge available to match the unique combination of instantly and automatically translating angular measurement onto a linear interface using multiple upright plate sections connected directly with a slidable indicia plate engaged with a grooved frame. Prior art have shown that many of these devices incorporate a protractor method of measurement and display. These gauges are generally slow and inconvenient to use, require both hands to operate, and are not easily portable.
There have been many protractor-type gauges, as disclosed in U.S. Pat. No. 2,607,121 to Wiedebusch and U.S. Pat. No. 4,744,152 to Roach, which are considerably different from the present invention, in that they do not utilize multiple upright plate sections hingedly connected to each other and hingedly engaged to a slidable linear indicia slide plate.
Fischers gauge [U.S. Pat. No. 4,513,512] utilizes a pair of linear indicators attached to a pair of arms pivoted about a common shaft and utilizes a complex driving mechanism consisting of gearwheels, transmission, and belt drives.
The various rafter gauges discovered are tools designed to perform specific tasks. Gardham's tool [U.S. Pat. No. 2,090,835] incorporates parallel arms with protractor-type indicia. Furlong's device [U.S. Pat. No. 4,462,166], and Levre's gauge [U.S. Pat. No. 4,328,619] are essentially pitch and length indicators to measure roof slope and other related rafter layout tasks and cannot measure related and included angles of related surfaces. None of the references show a plurality of upright plates hingedly connected with each other, hingedly connected to a linear indicator, and hingedly engaged with a frame.